Global comparison of HuR association with mRNAs triggered by IR (1 Gy, 6 hours) in ATM wild-type (GM02184^+/+) and ATM null (GM03332^−/−) lymphocytes. (A) Venn diagram comparison of mRNAs whose association with HuR was significantly (Z-ratio difference values > or < ± 1.5; P < .05) increased (red) or decreased (green) in IR-treated compared with untreated (Ctrl) cells. (B-C) Examples of genes demonstrating different association with HuR in response to IR in ATM wild-type and ATM null cells. Clusters of genes showing the biggest differences in association with HuR, measured by Z-ratio values. Values increase from green to red.